If you look at only the low frequency information of an image, you might be able to recognize the image, but it will not hold any precise detail. In other words: shadows and light areas, colors and tones. Low frequencies are the image data that contains information about volume, tone and color transitions. High frequencies in an image will contain information about fine details, such as skin pores, hair, fine lines, skin imperfections (acne, scars, fine lines, etc.).

Like in music any audio can be represented in sine waves, we can also break up an image into low and high frequency sine waves. Typically, we break down the information data in our images into high and low frequencies. There can be any number of frequencies in each image, and each frequency will contain certain information (based on the size of the details). One technique often used to deal with those 'shiny spots' as well as many other skin blemishes is called frequency separation.įrom The Ultimate Guide To The Frequency Separation Technique:įrequency Separation technique is virtually a process of decomposing of the image data into spatial frequencies, so that we can edit image details in the different frequencies independently.

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